Where Does the System in System Windows Show, and How Does It Differ from Ordinary Windows?

The core of 'system' is the coordinated design of overall performance, shown in: component matching — profiles, hardware, gaskets and glass pass lab cycle tests (e.g. hardware 100,000 cycles without fault), while ordinary windows are bought and assembled piecemeal with unstable performance; technical standardisation — system windows follow a fixed technical system (e.g. German passive-house standards) with unified chamber structure, thermal-break specs and seal layers, while ordinary windows rely on the maker's experience with arbitrary specs; performance reproducibility — the same system performs consistently across projects, whereas ordinary windows vary with workmanship.